System for producing electric power from renewable sources and a control method thereof

a technology of renewable sources and electric power, applied in the direction of dc source parallel operation, circuit arrangement, transportation and packaging, etc., can solve the problems of real dc/ac converters not being able to guarantee, oscillation of points, and consequent degradation of mppt efficiency, so as to reduce the drawback and maintain the preferential point of operation.

US7952897B2Inactive Publication Date: 2011-05-31MARICI HLDG THE NETHERLANDS BV
3 Cites 183 Cited by

Patent Information

Authority / Receiving Office
US · United States
Patent Type
Patents(United States)
Current Assignee / Owner
Publication Date
2011-05-31
Estimated Expiration
Not applicable · inactive patent

Smart Images

  • Figure 1
    Figure 1
  • Figure 2
    Figure 2
  • Figure 3
    Figure 3
Patent Text Reader

Abstract

Described herein is a system for generating electric power, comprising: an electric-power source (1) having a preferential point of operation; a double-stage inverter (3A, 3B), which transfers the energy from said source to an external a.c.-voltage electrical network (9); a block (5) for identification of the preferential point of operation, which supplies a reference signal according to the conditions of operation of the electric-power source and to the preferential point of operation of said source; a corrector block (10), provided for setting the parameter for control of the boost converter (3A) of the double-stage inverter (3A, 3B) as a function of the reference signal and of a signal of actual operation of said electric-power source, and for maintaining the source in the proximity of the preferential point of operation.
Need to check novelty before this filing date? Find Prior Art

Description

TECHNICAL FIELD

[0001] The present invention relates to improvements to systems for producing electric power from renewable sources, such as for example (but not exclusively) photovoltaic panels. In particular, the present invention relates to improvements to methods and devices for the control of systems for producing electric power, which have the function of maximizing the extraction of power.

[0002] More in general, the present invention relates to the control of sources of electric power that have a preferential point of operation, which is correlated to a parameter that can vary as a function of a non-controllable event. In the case of photovoltaic panels, said preferential point of operation is typically represented by the point along the current-voltage curve, which supplies the maximum power that can be supplied by the field of photovoltaic panels. This preferential point of operation varies as the insolation, i.e. the solar power incident on the field of photovoltaic panels, v...

Examples

Embodiment Construction

[0056]FIG. 6 shows a block diagram of a converter for photovoltaic panels modified according to the present invention. With the same notation used in FIG. 2, designated by 1 is the field of photovoltaic panels and by 3 the converter comprising an input or boosting stage 3A, and an output stage 3B of interface to the network, which is represented schematically by a voltage source 9. The stage 3A is constituted by a DC / DC converter, which sees to boosting the output voltage of the field of photovoltaic panels 1 to the programmed input bulk voltage (Vbulk) of the second stage 3B, which is constituted by a DC / AC inverter. Designated as a whole by 5 is a control block that executes an MPPT function, and designated by 7 is a block for controlling the DC / AC inverter, which maintains the current at output from the inverter in phase with the network voltage, the electrical network being schematically represented by a voltage source 9. The control block 7 comprises the output-current-phase co...